How to remove REALLY difficult stains from porcelain tiles.

Recently we received a tricky complaint from a customer. The plain grey colour porcelain tiles we supplied had been installed in a commercial store where mobile display racks on soft black rubber castors were used. Small greasy looking stain marks had developed under the castor wheels and cleaning staff had been unable to remove them. Stains appeared two days after the castor was put in place on a test tile with a load.

Below you can see two stains that we reproduced using the same castors and the same tiles. 

We did some research and contacted a local company TFC. Tile and Floor Care is a retail supply company that focuses on providing the retail market with high quality floor & tile cleaning products.

At first they recommended TFC Purge which is a specially formulated liquid paste designed to purge dirt and spots from polished porcelain floors. Purge has the ability to release stubborn dirt such as rubber mallet marks, pencil marks and scuff marks from the minute capillaries in polished porcelain. Purge must be used to spot clean before the general clean that is necessary as preparation for sealing. Purge may also be used to remove tough wax coatings that are applied to some polished porcelain during manufacture. Purge is safe and easy to use. Purge is used as is without dilution.

We thought this would do the trick, especially given the reference to rubber mallet marks but... nope. The stains remained even after a post purge cleaning with...

TFC Easy Clean is a powerful alkaline degreaser and neutraliser. Easy Clean must be diluted as instructed for general cleaning purposes. Easy Clean is specially formulated to cost effectively clean floor and tile surfaces that have been soiled with oils, greases and general grime. Easy Clean is free from ammonia and phosphates and is non-abrasive. Easy Clean is also used to neutralise tile and floor surfaces after they have been washed with acids. Easy clean is diluted according to how heavy the dirt is from 1:20 for general cleaning to 1:5 for very heavy grease.

We asked TFC for further recommendations and they suggested...

Sealer Stripper. This product is a very powerful solvent based stripper designed to remove most types of sealers and paints from the floor, including linseed oil and urethanes. Sealer stripper is used undiluted and left on the floor for five minutes before being wiped off and rinsed with water. It is toxic so should be used with care. We poured a teaspoon of the liquid onto each of the stains and left it for 5-10 minutes.

Success! When the tile was cleaned off and dried there was no evidence of the marks. We then cleaned the tiles again with EasyClean.

The U.S. Government Services Administration (GSA) is responsible for inter alia, the maintenance of government buildings. They recommend as policyusing Sodium Carbonate (Na2CO3) an acid or Sodium Hydroxide (NaOH) an alkali (caustic soda) for cleaning stubborn stains on tiles.

As always with difficult stains test a small unobtrusive area with a new product before applying to the entire floor.

Rustic Look and Quarry Tile

Quarry tile is unglazed ceramic tile. It is an inexpensive, durable and natural option for residential, commercial and even industrial tile applications. Quarry tile is used in industrial settings because it is so durable and can also be used outdoors. It has some other great qualities as well, such as being less prone to showing chips and scratches because the colour goes throughout the tile. In colder climates, freeze-resistant grades of quarry tile are used to prevent weather-related problems. but, like almost all tile types, quarry is porous, which means that it can become stained. If you install quarry tile in a kitchen it is really important to apply a glaze-like seal or wax finish to help prevent stains especially from oil. The color selection is not as vast as with other tile types, but there are several shades of red, orange, brown and gray., all of which exhibit a degree of colour variation creating a very natural rustic appearance. In residential applications, quarry is used for kitchens and pathways because it has a naturally coarse surface, making it less slippery when wet. Strong mortar and grout is used during installation to ensure a strong hold between the tile and the floor. Use limited amounts of water when cleaning unglazed or unsealed quarry. Too much water exposure can lead to mold growth especially in the grout.
The other option is to select an inkjet range of ceramic tile designed to look like quarry tile. These will be more water and stain resistant yet will still exhibit the rustic variation of natural tiles since multiple faces will be printed.

Contact us about rustic-look tiles, especially from our new Brasil Ceramica brochure, available on request only.

How to tell Ceramic from Porcelain.

Both porcelain and ceramic tiles are made from a mixture of clay and other materials which are pressed into a dense mass then kiln-fired at over 1000 degrees C. Although both porcelain and ceramic tiles are called “ceramic tile”, porcelain is by definition harder, denser and absorbs less water which is why it is less prone to cracking when exposed to cold. Specifically porcelain should absorb less than 0,5% of its volume in water. But how do you tell whether a tile is porcelain or ordinary ceramic? 1. Check the packaging. Look for the word “Porcelain”, a water absorption of <0,5% or a Mohs hardness rating of 7 or above. Ceramic tiles generally only have a water absorption of <3% at best. If the tile is marked ‘Polished’ it is likely to be porcelain. 2. Check the price. Porcelain tiles usually cost around 40% more than ordinary ceramic tiles and could be even higher depending on other technical factors. 3. Try the spit test for water absorption. Turn the tile on it’s side. Apply a little spittle to the edge. If it is absorbed into the tile within a minute or less it’s ceramic. On a porcelain tile the liquid will remain on the surface in a shiny meniscus for many minutes or even until it evaporates Porcelain tiles are generally made by the dust pressed method from porcelain clay like kaolin, which result in a tile that is denser and more durable than ceramic tile. The finish is a finer grained and smoother with sharply formed faces. Glazed porcelain tiles are much harder and are more wear and damage resistant than non-porcelain ceramic tiles. 4. Take a close look. Full body porcelain tiles carry the color and pattern through the entire thickness of the tile making them virtually impervious to wear and are suitable for any application. If the colour on the surface is the same through the cross section it is a good but not infallible indication that you are looking at a porcelain tile. 5. Compare the hardness. Ceramic tiles are softer and easier to cut than porcelain so if you are comparing two tiles the one that is easier to cut is probably ceramic. 6. Test the hardness. A more accurate way would be to actually test the hardness using a reference material. Hardness is measured using the Mohs scale which rates hardness from 1 (talc) to 10 (diamond). Ordinary ceramic tiles will have a hardness of 5-6 whereas porcelain will have a hardness of 7 or better. You can use the following commonly available materials to firmly scratch the tile. If the material leaves a distinct mark the tile has a hardness less than the test material · Penny (a bronze coin) - 3.0 · Knife blade (a good straight edged kitchen knife or penknife) - 5.0 · Glass (a broken piece of window glass) - 5.5 · Quartz (a sharp piece, available at new age lifestyle shops or a mineral scratch patch) - 7.0 ...and lastly 7. Contact the manufacturer and request a laboratory test report. Porcelain is classed B1a with a water absorption of <0,5% For any other inquiries about Porcelain or Ceramic tiles please drop us an email.   Ciao, The Link International team.